In recent years, disk apparatuses for recording taken pictures have been proposed for implementation by the use of a mass recording medium such as optical disks permitting random access.
In connection with such disk apparatuses, Japanese Patent Laid-open No. 2001-84705 proposes illustratively a method for creating an index file that indexes many files recorded on a recording medium, the created index file being recorded to the medium for use in handling the numerous files more easily.
Japanese Patent Laid-open No. 2002-278996 proposes a method for arranging files into a hierarchical structure using an index file created to index and record the files, whereby the numerous files may be handled even more easily than before.
Where the object to be managed by the index file proposed by the above patent documents is video content, a thumbnail is created from each of the files being managed. A series of entries representing the thumbnails are turned into a thumbnail entry file. A series of entries corresponding to those in the thumbnail entry file are made into a property entry file. Information for managing the thumbnail entry file and information for identifying the corresponding files being managed are recorded to the property entry file. Where the files being managed are files of video content, the index file allows the thumbnails recorded in the thumbnail entry file to be displayed so that the user may be presented with numerous items of video content recorded on the recording medium. Furthermore, what is recorded in the property entry file enables the user to acquire the video content represented by the thumbnail selected by the user from the video content presentations.
Conceivably, if the selection of files through the index file is utilized in deleting files as well, it will be possible to select any file desired to be deleted with ease and reliability, whereby the user's ease of operation in connection with the file-deleting chore will be improved. In this case, a desired file may be selected by resorting to an index file and deleted by a file management system handling the recording medium, followed by the deletion of the entry of the file in question from the index file.
Meanwhile, it might happen that the user later wants to restore some of the deleted files. However, it is not possible to restore the files deleted by the use of the index file.
One way to solve the above problem is by deleting only from the index file the entry of the file of interest while leaving the file itself intact on the recording medium. In this case, making another entry of the file recorded on the recording medium in the index file should enable the deleted file to be restored. This method, however, has the disadvantage of being incapable of detecting the file of interest from the index file because the index file no longer has the entry of that file. The difficulty in detecting desired files to be restored through the index file often results in the difficulty in restoring any deleted files in many cases.